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Bases are defined by Arrhenius as substances which release OH⁻ ions when dissolved in water. NO₂⁻ complies with this definition by the chemical reaction that is shown below:
NO₂⁻(aq) + H₂O (l) HNO₂ (aq) + OH⁻(aq)
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Answer:
No, the puddle was formed because of the sun, because if there was snow and it rained then it would have turned slippery or icy
Answer:
The pH of the buffer is 7.0 and this pH is not useful to pH 7.0
Explanation:
The pH of a buffer is obtained by using H-H equation:
pH = pKa + log [A⁻] / [HA]
<em>Where pH is the pH of the buffer</em>
<em>The pKa of acetic acid is 4.74.</em>
<em>[A⁻] could be taken as moles of sodium acetate (14.59g * (1mol / 82g) = 0.1779 moles</em>
<em>[HA] are the moles of acetic acid (0.060g * (1mol / 60g) = 0.001moles</em>
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Replacing:
pH = 4.74 + log [0.1779mol] / [0.001mol]
<em>pH = 6.99 ≈ 7.0</em>
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The pH of the buffer is 7.0
But the buffer is not useful to pH = 7.0 because a buffer works between pKa±1 (For acetic acid: 3.74 - 5.74). As pH 7.0 is out of this interval,
this pH is not useful to pH 7.0
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Answer : The partial pressure of nitrogen gas is, 2.94 atm
Explanation:
According top the Henry's Law, the concentration of a gas in a liquid is directly proportional to the partial pressure of the gas.


is Henry's constant.
or,

where,
= initial concentration of gas = 
= final concentration of gas = 
= initial partial pressure of gas = 0.78 atm
= final partial pressure of gas = ?
Now put all the given values in the above formula, we get the final partial pressure of the gas.


Therefore, the partial pressure of nitrogen gas is, 2.94 atm
Answer:
A. Move the buret clamp to a ring stand with a larger base.
Explanation:
The ring stands are used to hold burettes, light in weight to avoid loss of stability, that is why it is necessary to change the size of the ring stand so that it can support the buret that we are going to use. It is not recommended to balance it with the hand since it would give us an inaccurate result in the titration.